Analyses from the phase III ALSYMPCA trial showed that treatment with the alpha-emitting radiopharmaceutical radium-223 resulted in quality-of-life (QoL) improvements over placebo in patients with castration-resistant prostate cancer (CRPC) and symptomatic bone metastases.
“Patients with CRPC and bone metastases often present with symptoms such as pain fatigue, anorexia, and, rarely, spinal cord compression, contributing to rapid and significant deterioration in health-related QoL and mortality,” wrote study authors led by Sten Nilsson, MD, PhD, of Karolinska University Hospital in Stockholm.
The ALSYMPCA trial found that radium-223 prolonged overall survival (OS) as well as time to first symptomatic skeletal event by significant periods. The trial included prospective QoL measurements using the EuroQoL EQ-5D and the Functional Assessment of Cancer Therapy–Prostate (FACT-P). The results from these tests were published online ahead of print in Annals of Oncology.
The analysis was done in the intent-to-treat population, which included 614 patients randomized to radium-223 plus standard of care and 307 patients randomized to placebo plus standard of care.
More radium-223 patients had improved EQ-5D utility scores than placebo patients (29.2% vs 18.5%; P = .004), for an odds ratio (OR) of 1.82 (95% CI, 1.21–2.74). Similarly, 24.6% of radium-223 patients had a “meaningful improvement” in FACT-P total score, compared with 16.1% of placebo patients, for an OR of 1.70 (95% CI, 1.08–2.65; P = .020). The rates for FACT-P total score were largely driven by three of five subscales (emotional well-being, functional well-being, and prostate cancer symptoms).
There was no difference in improvements in utility score based on history of docetaxel therapy (P = .637), or based on current bisphosphonate use (P = .977).
Fewer radium-223 patients experienced a worsening of EQ-5D utility scores as well, at 36% vs 54% with placebo for an OR of 0.48 (95% CI, 0.34–0.67; P < .001). The proportion who experienced worsening QoL based on the FACT-P total score was not significantly different between the groups.
Treatment was found to be a significant predictor of utility score, and radium-223 was associated with higher scores than placebo (P = .002). This was also the case for the FACT-P total score (P = .004).
“QoL deterioration over time for CRPC patients is well documented, and may be a prognostic factor for more rapid disease progression,” the authors wrote. “Agents such as radium-223 that delay QoL deterioration or improve overall QoL and OS are valuable additions to treatment.”